NASA’s New Horizons spacecraft made a historic New Year’s encounter with an object nicknamed Ultima Thule in the Kuiper Belt a billion miles beyond Pluto. The probe passed around 3,500 kilometres from the mysterious object at 0533 GMT on New Year’s Day, making it the most distant Solar System body ever explored up close.

NASA’s New Horizons probe, racing toward a 1 January flyby of the Kuiper Belt body known as Ultima Thule, has given scientists their first major surprise: the oblong, or binary body shows no signs of a discernible light curve suggesting rotation.

NASA’s New Horizons spacecraft has finally caught sight of its post-Pluto target, a Kuiper Belt body nicknamed Ultima Thule. If all goes well, New Horizons will make a close flyby of the distant body on 1 January.

NASA’s New Horizons probe, three years outbound from Pluto, has woken from electronic hibernation, healthy and on course for a New Year’s Day flyby of an even more remote Kuiper Belt object nicknamed Ultima Thule.

Astronomers are searching for a presumed “Planet Nine” in the extreme outer solar system whose gravity could explain unusual orbits of several remote bodies. New research suggests Planet Nine may not be necessary.

Astronomers using ESO’s Very Large Telescope have discovered the first carbon-rich asteroid in the distant Kuiper Belt. The asteroid likely originated in the inner Solar System and was ejected by gravitational encounters with the Sun’s gas giants.